The present invention relates generally to data storage systems, and systems and methods to improve storage efficiency, compactness, performance, reliability, and compatibility. Enterprises often span geographical locations, including multiple corporate sites, branch offices, and data centers, all of which are generally connected over a wide-area network (WAN). Although in many cases, servers are run in a data center and accessed over the network, there are also cases in which servers need to be run in distributed locations at the “edges” of the network. These network edge locations are generally referred to as branch locations in this application, regardless of the purposes of these locations. The need to operate servers at branch locations may arise from variety of reasons, including efficiently handling large amounts of newly written data and ensuring service availability during WAN outages.
The need to run servers at branch locations in a network, as opposed to a centralized data center location, leads to a corresponding requirement for data storage for those servers at the branch locations, both to store the operating system data for branch servers, in some cases, for user or application data. The branch data storage requires maintenance and administration, including proper sizing for future growth, data snapshots, archives, and backups, and replacements and/or upgrades of storage hardware and software when the storage hardware or software fails or branch data storage requirements change.
Although the maintenance and administration of data storage in general incurs additional costs, branch data storage is more expensive and inefficient than consolidated data storage at a centralized data center. Organizations often require on-site personnel at each branch location to configure and upgrade each branch's data storage, and to manage data backups and data retention. Additionally, organizations often purchase excess storage capacity for each branch location to allow for upgrades and growing data storage requirements. Because branch locations are serviced infrequently, due to their numbers and geographic dispersion, organizations often deploy enough data storage at each branch location to allow for months or years of storage growth. However, this excess storage capacity often sits unused for months or years until it is needed, unnecessarily driving up costs.
Although the consolidation of information technology infrastructure decreases costs and improves management efficiency, branch data storage is rarely consolidated at a network branch location, because the intervening WAN is slow and has high latency, making storage accesses unacceptably slow for branch client systems and application servers. Thus, organizations have previously been unable to consolidate data storage from multiple branches.